The present invention relates to an improved composite structure that finds use in varied environs, exemplified by insulation, (thermal and sound), wall and window treatments, cushion pads, and the like, as well as apparatus and method for producing same.
Since the evolution of the knit stitch process, numerous and varied fabrics have been produced on knit stitch machines sometimes referred to as stitch bonding machines, as well as various warp knitting machines. In like fashion, fabrics have been produced heretofore on such types of machines where varied elements have been utilized in the construction of the fabric. An example of such is plural layers of webs or plural yarns atop various webs to afford certain structural and/or aesthetic qualities to the ultimate product formed by knit stitches thereacross. Additionally, materials other than fibers, webs or fabrics have been used exemplified by metal foils, polymeric films and the like. Likewise, on certain stitch bonding machines such as a Maliwatt machine, a fleece or web of fibers has been fed through the throat of the machine where the web is knitted across its width to impart additional or initial integrity to the fleece or web.
In the examples set forth above, the primary thrust of the exercise has been simply to provide an alternative or modification to conventional knitting to provide a fabric structure for various specific functional and/or aesthetic purposes. The fabric structures produced have included one or more layers or substrates held together in a juxtaposed orientation by a thread system of knit stitches.
According to the teachings of the present invention, however, plural preformed substrates are included, but which are bound together while being held apart to achieve a different level of functionality for these general types of goods. The only knitted structure of which applicants are aware that is even close to structures according to the present invention are certain fabrics produced on raschal machines, referred to as "spacer fabrics." Spacer fabrics are formed by the knitting of two layers of knit structure and the spacing part of the knit structures by portions of the knitting thread. Not only is such a fabric and system of production limited to unitary knitted structures, the process by which they are produced is very slow. On the other hand, a composite according to the present invention is limited only by materials capable of being pierced during the knit stitch process, and the machines on which the composites are produced are capable of higher production rates than the raschal machines. Hence, composites according to the present invention are vastly different from the raschal "spacer fabrics."
While as noted above, widely varied fabrics and/or fabric constructions or fabric composites have been heretofore produced, composites according to the present invention have not previously been produced, nor are the apparatus or process for producing same taught by or obvious in view of the prior art.